Silence a microwave with simple panel

I would like to mute the beeping on a Sharp 75MR microwave. I have read that many microwaves can be silenced by holding the 1 or 0 button, or with secondary keys, but this has a very simple panel with only 10 minute, 1 minute and 10 seconds buttons, plus some pre-sets. Holding the number or pre-set keys does nothings, and holding stop activated the child lock.

It came with my employer-provided accommodation, so I’d rather not do something permeant to it, but I’ll disconnect the speaker if that is the only option. The manual has nothing on this topic.